Group B coxsackievirus diabetogenic phenotype correlates with replication efficiency

Area of Science:

• Virology
• Immunology
• Endocrinology

Background:

• Group B coxsackieviruses (CVB) are known viral triggers for autoimmune diseases.
• Type 1 diabetes (T1D) is an autoimmune condition characterized by the destruction of pancreatic beta cells.

Purpose of the Study:

• To investigate the role of different Coxsackievirus B3 (CVB3) strains in initiating type 1 diabetes (T1D) in nonobese diabetic (NOD) mice.
• To determine the relationship between viral replication, infectious dose, and T1D onset.

Main Methods:

• Inoculation of old NOD mice with different strains of CVB3 (CVB3/GA and CVB3/28).
• Detection of viral proteins in pancreatic islets post-inoculation.
• Assessment of viral replication kinetics in the pancreas and beta cell cultures.
• Genetic manipulation of CVB3 strains by exchanging 5'-nontranslated regions.

Main Results:

• High doses of poorly pathogenic CVB3/GA rapidly induced T1D in NOD mice.
• Viral proteins were found in islets, associated with beta cells and other islet cell types shortly after infection.
• The virulent CVB3/28 strain showed faster replication in the pancreas and beta cell cultures compared to CVB3/GA.
• Exchanging 5'-nontranslated regions affected viral replication in beta cells and suppressed in vivo replication.

Conclusions:

• CVB strains can induce T1D in prediabetic NOD mice.
• T1D onset is significantly influenced by the viral replication rate and the infectious dose.
• Viral factors, including replication kinetics and specific genetic elements, play a crucial role in CVB-induced T1D.